Antenna Recommendations; Antenna Separation - Sierra Wireless AirLink ES Series Hardware User's Manual

AirLink ES Series Hardware User Guide
30
The included antennas are for indoor use only.
When placing either the included antennas or third-party antennas, follow the
antenna separation guidelines in
performance.
If you want to use a third-party antenna placed outdoors, Sierra Wireless
recommends working with your authorized distributor to provide the proper
protection, which may include an RF lightning arrestor and/or Ethernet surge
suppressors. The antenna must be installed by qualified personnel.

Antenna Recommendations

Note: Do not remove the secondary antenna. It helps the ES Series device achieve the
maximum network coverage. The ES Series device works without one installed, but with
reduced network coverage.
Note: If the antennas are located far away from the ES Series device, keep the cables as
short as possible to prevent the loss of antenna gain.
Warning:
In more complex installations (such as those requiring long lengths of cable
and/or multiple connections), you must follow the maximum dBi gain guidelines specified
by the radio communications regulations of the Federal Communications Commission
(FCC) or Industry Canada or your country's regulatory body (if used outside the U.S.A.).
Also see Important Information for North American Users on Radiation Exposure
page 51 for more information.

Antenna Separation

Inadequate antenna separation between the primary and secondary antennas
creates unwanted interference that can cause reduction in:
• Antenna efficiency
• Transmit power
• Receiver sensitivity
• Data throughput
• Radio front-end life span
Antenna separation recommendations:
• The antennas should be separated so that there is at least 10 dB isolation
over the entire operating frequency range.
• The separation should be at least 1/4 wavelength (), but preferably
1/2 wavelength () or greater of the lowest operating frequency. See
for specific recommendations, based on your network type and frequency.
Antenna Separation on page 30 for optimum
on
Table 3-1
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